This invention relates to an improved surface grade railroad crossing structure.
One prior art structure is exemplified in U.S. Pat. No. 4,093,120, which discloses a railroad crossing structure having a gauge structure (located between the rails) consisting of two separate pads. Two pads are required in order to properly install the structure between the ties. Manufacture of two separate pads, however, necessarily involves an increase in manufacturing costs and thereby a corresponding increase in cost. Also, two pad structures become uneven at their center juncture, thereby creating a crack through which moisture may enter and be retained, resulting in deterioration of the substructure and ties.
Another prior art structure is exemplified by U.S. Pat. No. 4,289,273, which discloses a railroad crossing structure including pads of widely varying shapes to be used in the vicinity of track switches, frogs and intersections. Each of these pads must be individually manufactured since each pad is sized to fit a particular section of the track. Installation thereof is also greatly complicated since each of the pads must be identified with a corresponding section of rail.
In addition to the above problems is a difficulty in the prior art with adequately securing pads to prevent lateral and vertical movement, resulting in grade crossing structures which are not solid and unitary and which do not block water and debris and filtration into the railroad bed.
The present invention is directed toward overcoming one or more of the problems as set forth above.